学进去

阅读短文，根据短文内容完成文后的句子。

Endangered dolphins are beautiful animals that need to be saved. However, if we continue to do the same about the environment, many of the wonderful creatures are going to die out.

It may be interesting that there are about six different types of dolphins that are endangered. Many of them are river dolphins and they are almost lost forever if we do not take the time to care for them. The following are the reasons why they are in danger.

One problem that has caused endangered dolphins is fishing nets. Dolphins can often get stuck in these nets and they may die. Another problem is the fact that many people and different countries will hunt for dolphins as food.

The next problem is pollution. When the oceans and rivers are polluted, it affects the very environment where these beautiful creatures are living. It may be important to also keep in mind that the dolphins are towards the top of the food chain. Because of this, they are going to eat smaller animals in the water. If these smaller animals are affected by the pollution as well, there really is no safe place for the dolphins to go.

We have to do something to protect them. You can also pay attention to the land around you. Do not litter and stop if you do. Spend time on the weekend cleaning up trash in your area and recycle what you can. You play a large role in this whether you believe it or not. So, find out what you have done to endangered dolphins and work towards a positive change.

1．Many river dolphins are almost ________ if we don’t take care of them.
2．The three problems that have caused endangered dolphins are ________.
3．The dolphins are to the top of ________ and kill smaller animals for food in the water.
4．If we ________, we will play a large role in protecting dolphins.
5．The passage mainly tells us that ________.